Automatic telephone system.



A. E. STEVENS. AUTOMATIC TELEPHONE SYSTEM. APPLICAIION HL'ED JAN. \7. I916 PatentedSept. 24,1918

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2 SHEETS-SHEET lawenioaf r 0 Wm M B A. E. STEVENS.

AUTOMATIC TELEPHONE SYSTEM. APPLICATION FILED JAN. n. 1916 P tentedse u 24,1918.

. m? N NIQ WENN NQ Invenib 'mAi/i'ariz'y t UNITED STAT s PATENT OFFICE.

ALTON E. STEVENS, OF PROVIDENCE, HODE ISLAND, ASSIGNdR TO SCREW MAGHIN PRODUCTS CORPORATION, OF PROVID ENCE, RHODE ISLAND.

AUTOMATIC TELEPHONE SYSTEM.

Speclflcation of Letters Patent.

Patented Sept. 24, .1918.-

1 b all whom it may concern:

Be it known that I, ALTON E. STEVENS,

a citizen of the United States, and a ,resident of Providence, in the county of Providence and State of Rhode Island, have invented a new and useful Automatic Telephone System, of which the following is a specification.

My invention relates to that class of auto matic telephone systems primarily designed for private installation and limited in the number of iossihle connections, and has for itsohject tlie simplifying of telephone apparatus of this class, to reduce the number of operations necessary in making the connections from one telephone to another, and to eliminate as: far as possible causes of faulty operatioln The principal features of my invention relate to the means whereby several stations may become electrically united for the pur pose of inter-cinnmnnioation, whereby so crecy is secured for those parties so con'nert ed; whereby battery power may be supplied to the entire system for communicating and. ringing purposeshy one common battery; whereby all stations may be automatically simultaneously signaled, from any station; and whereby such other results may be attained-ms may hereinafter appear;

In the drawings, Figure 1 represents the central stutiornshowing the mechanism associated with three telephone lines, together with the electrical circuits connected there with. Fig. 2 represents three telephone stations in conjunction with the central station shown in Fig. 11; both figures are in diagram-' inatic form.

The following description covers the most approved embodiment of my invention and its operations as they take place.

To assume that a party at station A,.Fig.

2, wishes to call a. party at: station C. The:

firstopcration for thewcall'ing party is tot ,turrl-the impulse wheel 1in a clockwise di- .ground 11. This causes the holding ma can best be explained by describing in detail erection a distance which will cause the.

tension of a suitable spring 110. While the impulse wheel 1 returning to its normal position, the. spring 3 makes contact with spring 4. three times, thereby closing a. select mg (f-ll'ClUt from ground '11 through springs T, and 8 which will. come in contact u on the removal of the receiver .5, through t e wire 12, the springs 3 and 4:,"th' wire 13, the selecting magnet 14, Fig. 1, to battery 15 and ground 16. The selecting magnet 14 is. thereby energized three times, and attracts its selecting armature 17, causing. the pawl 18 connected therewith to engage threeteeth in succession in the ratchet wheel 19, therebystepping brush. 20 to the third contact point 43 in the contact bank 2]. which contact point is'cmmectcd; by bank wire 44 to the selector and telephone of Stati0l1 C.

At the first step from ormal position of the rutclwt Wheel 19, the holding detent 21" caused to engage the teeth in said ratchet and hold, it at each successive step in the-fol lowing manner; As said ratchet Wheel. first HIGVQS"L'U]K1 normal position its arm 22 has disengaged the spring 23, thereby permitting to make contact with spring 25, establish ing a holding circuit through the-holding magnet as follows: from "ground 26 through battery '27, the magnet 28, the springs and 23, the wires 29 and 30, the transmitter 31, Fig. 2, the receiver 5, the wires 32 and 12, the springsi8 and 7 to the et, 28 to be energized andattract its hol ing armature 33, thereby permitting the detent 21 to engage the ratchet wheel by the, pres, sure of a small spring 111. l i

i This holding armature 33 carries'an ex:-

sion 3 t on the spring 35. The tension ofthe spring .353, however, is so great that the amountof current flowinpf through the coils of the magnet-28 is not sullic'ient to energize this magnet sufliciently to attract the armatore 33 to move the spring 35 out of contact with the spring 76. 'While the springs 3 and .4 are in contact for the last of the series ofselecting impulses, the ringing pin 36, on the impulse .wheel 1 causes the ringing spring 37. to make contact with the spring 38, thereby shortcirouiting the transmitter 31 and receiver 5, and by reducing the resistance in the holdin circuit, causing an additional mount 0, through the'c'oij s ot the holding magnet 28,,"

,tension which engages an insulated ems-y current to flow hereby increasin its energy to such a deree as to cause the holding armature 33 to overcome the tension of the spring 35, whereby the spring 35 breaks contact with the spring 76 and makes contact simultaneously with the springs 41 and 42. The contact between the SpI1IlgS-37 and 38 being broken, when the impulse wheel 1 comes to rest at ts normal position, the transmitter 31 and receiver 5 are a ain brought into circuit with the coils o the magnet 28, and the amo'iint of current .flowing in this holding circuit is decreased. This current, however,

9 is sufficient to cause the magnet 28 to hold the armature .33 after it has once been attracted.

Thexcontact between springs 37 and 38, Fig. 2, made as just descrlbed completes a ringing circuit, whereby the ringer at station O is operated, this ringing circuit being as follows: from the ground 11 through springs 7, 8, 37 and 38, the wires and- 64, Fig. 1, the springs 39 and 40, 41, and

. 42, to the brush 20 which is in contact with 25 the point 43, bank wire 44 and the wire 45 I of station C, the springs 46 and 47, the .wires 48' and 49, Fig. 2, the ringer 50, the springs 51 and 52, the wire 53, the selecting magnet 54, Fig. 1, the battery 55-, and the ground 56. The ringer is of high resistance, and the selecting magnet 54 is of low resistance, this latter being adjusted so that it will not operate through the resistance of the ringer.

The party at stat-1on0 upon receiving'his signal removes the receiver 57 from the hook 58 and can now communicate with the 'partyat station A over the vfollowing talking circuit: from the ground 11 through 40 springs 7 and 8, the wires 12 and 32, the

receiver 5, the,t .ransmitter 31, the wires 30 and 64, Fig. 1', the springs 39 and 40, the springs 41 and 42, to the brush 20 and contact point43, bank wire 44, Wire 45, springs 5,46 and47 wires 48 and 49, transmitter 61,

'Fig. 2, receiver 57, wires 62 and 63, springs 59 and .60 toground 94. The, springs 59 and 60 are brought in contact with each other upon the removal of the. receiver 57 from the hook 58 which is, drawn up by the small spring 112. v

' Battery power is supplied to energize the transmitters and receivers at each station as follows: from ground 26, Fig. 1, battery 27 through the magnet 28, the springs 25 and 23, the wire 29, to th-e. wire 30, Fig. 2, thence over the wire 30 to station A, and over the wire 64, Fig. 1, to station C."

Station's A and C having finished communica-tion, thefrconnction is discontinued by plaeingthe rqcejiver 5 on the hook 6,

, thereby breaking \cennection between the springs 7 and 23, causing the holding magnet 28 to become cleenergized, whereupon- J6 its armature'33 is lelcased and causes the has moved from normal position, as shown,

the arm, 66 has allowed the spring 47 to break contact with spring 46, and spring 67 to make contact with spring 46, thereby completin a busy tone circuit from round 73 through battery 72, interrupter (l and 70, busy tone .magnet 69, bus-bar 68 to sprin s 67 and 46, wire 45 and bank wire 44. his circuit being established, when the brush. 20, for station A, reaches the point 43 connected with bank wire 44 in connec tion with the selecting impulses of station A, the busy tone circuit was established as just described to the brush'20, springs 42, 35, 41, 40 and 39, wires 64 and 30, Fig.

.2, transmitter 31, receiver 5, wires 32 and party at station. A that station C is in use.

,If upon the attempt of station A to establish' a connection, station C had been busy by reason. of its having been called by another station, as B, station A would have been prevented from communicating with station C in the vfollowing manner:

The bank wire 44, Fig, '1, in its normal state is not grounded, but when connection is made to this bank wire for the purpose of calling its associated station, this .wire is grounded over the following circuit: from ground 11, Fig. 2, to springs 7 and 8, wires-12 and 32, receiver 5,-transmittcr 31', wires 30 and 64, Fig. 1, springs 39, 40, 41, 35 and 42 to brush 20 and contact point 43; thence to bank wire 44. Now assuming that bank wire 44 has been grounded in this manner by a station other than A and that station A attempts to connect with bank wire 44 and its associated-station C, station A willbe prex' ented from doing so in the following manner: As the ratchet .wheel 19 lo e of station A is stepping around so that the brush 20 has passed the contact point 84,

the spring 74 is permitted to make contact with spring 7 5, thereby establishing a lockout relay circuit from ground 719, battery 7 R, lock-out relay magnet 77, sprlrigs 76 and 35, 75 and 74, to brush 20, an point 43 connected with bank-wire 44 which is already groundedby reasonjofg 's'tation C thence to having been called by the other party, as heretofore described. The lock-out relay magnet 77 thereby becomes energized, and attracts its armature 83, thereby completing a holding lockout circuit from ground 79, battery 78, magnet 77, springs 81 and 82, and 74, brush 20, contact point 43, and wire 44; which is noW grounded, The mag net 77 will, therefore, remain energized un til the ground is removed from wire 44 or --until the brush 20 returns to its normal po sition. During the time this magnet is energized, a busy tone circuit is maintained from ground 73 to battery 72, interrupter 71 and 70, lna net 09, bus-bar 08, wire 95, springs 80 am, 30, wires 6- and 30, transmitter 3]., receiver 5, wires 32 and 12, springs c and 7 to groundll. The interrupter 71 and 70 is thus caused to operate, and causes a buzz in the receiver 5 over this circuit just described. The calling party, in, this case station A, is thereuptm notified. that station. is busy, and replaces his re ceiver 5 on the hook it.

It is many times desirable to locate a. party who is not at his usual telephone station but may be near some station on the system. To facilitate this, I provide a general call or signal system. made up of a series of bells or other signaling devices, as 93, Fig. 1, which may be placed in various places served by the system and operated from any telephone. station. In'such a case as this, it a person at station A had called for example station B, received no response by reason of the person usually at station B bein away from said station B and his wherea Jouts being unknown to the calling party at station A, the party at station A. will operate his selecting device in such a manner as to cause the brush 20 to make contact with the point 84 which is connected to bank wire 85 .and signal relay '80, by means of which a code signal may be sounded on the signal device at the will of theparty calling.

g The signal relay circuit just referred to is as follows: from ground 11', Fig. 2, springs 7 and 8, wires 12 and 32, receiver 5, transmitter 31, wires 30 and 64, springs 39 and 40, 41, 35 and 42, brush 20, contact point 84, wire 85, magnet 86,'battery 87 to ground 88. The resistance of the receiver 5 and thetransmitter 31 is such that suflicient cur rent is not permitted to pass through the magnet 86 to energize the same to a sutlicient degree to cause it to attract its armature 89. However, whenever the receiver 5 and the transmitter 31 are short circuited, as when, at the calling station, the s rin s 37 and 38, are momentarily closed, y t e ringing pin 36 on the ratchet impulse wheel 1 returning to norma'l position; or as when" the springs 99 and 100 are manuallgl pressedby the button 98, Fig. 2, to give a c aracter- 0 is not prevented upon t istic call, enough current flows through signal relay magnet 86 to cause it to attract its armature 89. This closes a circuit, including battery 90 between the wires 91 and 92, thereby o crating the signal devices 93 which are bri ged between these wires. The party, desired, thus receives an automatic warnin call, and a, manual characteristic call, an upon hearing his signal, may con verse with the garty calling from any station, such as C, y so operatln such station as tocause the brush 101 to e brought in contact with point 102, and hence with bank wire 85 which is also connectedwith the point 84 of the station callipg.

It should "be noted that whenever any station becomes connected to the line 85, either for calling, or for answering a call, a. single ringing impulse is sent through the ringing relay 1n it, as through the contact of the springs 37 and 38, by the return of the ring ing pin to normal position, and any station responding to the call will send in a like signal through all of the signaling devices; so that should the callin party desire to leave the receiver off the 00k, and attend to other matters, the station, on responding, would send an automatic signal that he was ready to converse.

It should be noted also that although the bank wire 85 is rounded by reason of its having been calle b station A, yet station fi -om connecting to this same bank wire 85 by my lock-out device, for the reason that the springs 103 and 104 do not make contact until the brush 101 has passed contact 102, and as the circuit of the lookout relay 105 of station C depends upon the contact between these springs for its energizing current, it is apparent that this lock'out relay will not act to prevent connection to any line, unless the springs 103 and 104 are in contact with each other.

Having now described that operation of my automatic telephone s stem, I. claim- 1. In an automatic telep one system, telephone lines, automatic means whereby a callin I niacte with any other line for the pur ose of communication, means whereby both mes may be supplied with electric current to the transmitters and-receivers at the connected stations: a ringing circuit with it suitable source of current; aspring operated ,impulse wheel at the calling station; a pair-of contact springs in the ringing circuit; a ringing pin on the impulse wheel; to "close-momentarily said springs, after the impulse ratchet wheel has sent its last selecting 'impulse; a" tcle hone hook switch with a s rin catch norml engagingtheteeth o sai impulse aprin grounding contacts,

one grou r ed, and t e other connected to the rin'- rmoval of the receiver from the circuit; and means whereby,

line may become electrically conmeans hook switch, said ounding contacts become aged, and t e spring operatedimpulse -w eel released, to cause the calling and called-lines to become connected, and to cause the ringing pin to close momentarily the ringi circult through the rin in springs an give a single signal at the ca le station. I

2. In an automatic telephone system having telephone lines, and connecting means whereby a calling line may become automaticallyconnected to another line :a selectin circuit with a suitable source of electricsfi current; a selecting magnet in said circuit; a selecting armature to step. said connecting into operative position; a holding circuitvyith a suitablesource of electrical current;,a holding magnet in said circuit. and an armature to hold in, and release irom, said connected position, said connecting means; a telephone hook switch whereby the selecting circuit may be rendered operative, and the holding circuit may be grounded, upon the removal of thereceivcr from the hook switch, andrelnain grounded until the receiver is replaced upon the hook switch.

3. In an automatic telephone system having telephone lines, and connecting means wl lereb a calling line may become automatical y connected to another linct--a selecting circuit with a suitable source of current; a selecting m'agnet in said circuit; a selecting armature to step said connecting means into operative position; a holding circuit with-suitable source of current; a holding magnet in said circuit, and an ar-- mature to hold in, and release from, said connected position,- said connecting means; a telephone hook switch whereby the selecting cirzuit may be rendered operative, and the holding circuit'become grounded, upon the removal of the receiver from the hook switch, and remain grounded until the receiver; is replaced upon the hook; the tele phone receiver being in the holdin circuit; :1. pair of contact springs in the 'hoflling circuit; and automatic means to causethem to make momentary contact, after said calling liuc has become connected to :1 called line, to sliol't-circuit said" transmitter and receiver niolilentari1y, tofenergizc, sullicienl'ly, the

' receiver,

66 hav ng assigns. ing relay ,there1n,' "an d.a point contact jspr i ngionegrounded and-ithe other' lmlding, magnet to cause its armature to 11love toward it and to overcome the tension of armature springsof suidholding magnet, and; to he there retained by the magnetic field due to the reduced currentby reason of theno longer short circuited transmitter and I 4., In'an automatic telephonesystem. ha ing telephone lines, and stations therewith, and vautomatic means for each station whereby one of said stations may be-; come connected with anotherza'source of electrical ener a signalin relay circuit connected of contact in each ofsaid automatic means, whereby any one or more stat ons may become connected in a-talkmg'clrciiit; a signalin elec tric circuit having therein, wheropened, a characteristic number of times for'the purpose of correspondingly-energiz-" ing the signaling relay and causln' its armature to make and interrupt the signaling circuit, and o crate the signaling devices as required; ,an automatic means whereby the signaling relay is operated whenever a calling station becomes connected to the signaling relay circuit. l

5. In an automatic telephone system. having telephone lines and stations' connected therewith, and automatic means for each station whereby any one of said stations may become connected with 'another:-a source of electrical energy; a naling relay cir-- :iauit having a signaling re ay therein, and a point of contact in each of; said automatic means, whereby any one or more of said'stntions may become connected in a talking circuit; a signaling electriccircuit having therein wherever desired, si alingdevices, and the armature of a signa ng relay; a transmitter and a receiver being in the signaling relay circuit; springs and a-press button in the signaling relay circuit, with which to short circuit the-transmitter and the receiver and permit enough current to pass through the signaling relay to energize it, said button thereby controlling the signaling relay circuit to cause it to close and open the signaling relay circuit, and the signaling circuit for the purpose of causing the signaling devices to give the characteristic signal required; and automatic means whereby the signaling relay is operated whenever a call ing station becomes connected to the signaling relay circuit.

6. In an automatic telephone system has ing telephone lines and connecting-menus whereby a calling line may become automa ticully cormcctcd with. any other line for the purpose of c1uuluunirationza selecting cir; ruit with suitable source of electrical c||rrent; a holding circuit with suitable source of electrical current; a ringing circuit hawmg a suitable source of current; an impulse wheel at the station "of the calling line; a

telephone switch provjided with a spring to movably hold the impulse wheel in the position to which it is manually moved; contact springs in the select-mg circuit, normally.

open, but operated .bythe teeth of the, re-. leased lmpnlse wheel; contact springsin, the ringing circuit normally open; a ringing pin on the ratchet wheelito close, momentarily the ringing contact springs; two grounding the required eonnectim connected with the selecting circuit, the holding circuit and the ringing circuit; means whereby a removal of the telephone from its hook switch, enuses the grounding springs to make conlnet, and the hook switch spring to disengage the impulse wheel, permitting the latter to rot urn to normal position, and cnusin 10 selecting springs to contnet the desire number of times to scml impulses over the selecting circuit; and then before stopping at normal position, causing the ringing pin n'iomenturily to close the ringing circuit to signal the calling station; the hohling circuit remaining closed until the receiver is replaced upon its hook switch, when the 'grounil contact springs separate and break the holding circuit.

In witness whereof 'I have hereunto sell my hand in lhc presence of two witnesses AL'ION l STEVENS. W itnesses:

Lonm M. (bolt, MAURICE Tl. Coon. 

